John Demko is the manager of the Resident Office at Vandenberg Air Force Base, California, for the Launch Services Program.

Demko has been with the Launch Services Program since 1994, initially as a Launch Site Integration Manager at Vandenberg supporting a variety of Earth and space science missions launching on an array of expendable launch vehicles for NASA and NOAA, as well as Department of Defense, commercial and international partner missions, including the first satellites for the countries of Argentina, Denmark, South Africa and Sweden. In 2003, he became the manager of the Resident Office at Vandenberg, representing the Launch Services Program to Vandenberg base leadership and tenants, as well as overseeing NASA's Delta II launch complex and resident team of 40 civil service and contractor personnel.

From 1988 to 1994, Demko served as NASA's ground operations manager for the Ben Guerir, Morocco, Transatlantic Abort Landing site for the Space Shuttle Program and shuttle payload operations manager for space shuttle missions STS-43, STS-45 and STS-57 at Kennedy Space Center in Florida.

An Ohio native, Demko graduated from Charles F. Brush High School in Cleveland, Ohio, in 1978. He completed a Bachelor of Science in mechanical engineering from Ohio University in Athens, Ohio, in 1982.

Demko lives in Santa Maria, California, with his wife Jeanne. He enjoys motorcycling, playing the drums, camping and hiking.